Forming tool for reducing stock



July 6, 1954 H. T. WRIGHT FORMING TOOL FOR REDUCING STOCK Filed Feb. 12, 1952 v INVENTOR.

Homer 7." Wrighf.

Patented July 6, 1954 RAIENI o.FF,Lc'.s-1

This. inventionrelates to refrigerating:appara-v tus andxmore particularlytoa method andatool'. forspinning tubular *sto'ck' for use iniabricating refrigerant filters and the like.

In manufacturing tubular housings for. filters and the like; itisr. standard practice .to place .a lengthof tubular stockin a holderuand to exertel -reducing pressure I on the stock by 1 means of. a spinningwtool asthe tubular stock' and the 'tool are relatively rotatedtand umoved toward each other. The spinning-tools used intheprocess are usually providedwith? arrannular portion which gradually decreases in cross-section and thereby exerts a reducing pressure-continuously around the entire circumference-of.-thestock to progres-- sively -heat the latter to -ian easy workable condition. Prior to :this invention it: wasconsidered necessary #to have the --'spinni ng device exerting very high pressure on the surface being shaped and to -engage the stock' -throughout amajor portion of thercircumference, whereas. it-has been discovered that aspinning tool having a plurality of properly designed'sto'ck engagin'gportions will effectively reduce th'e diameter of r the tubular stock even though the s'to'ck engaging portions contact the stock onl y throughout a minor portion of its circumferencei It is an object of this invention to provide an improved spinningdevice in whichaplurality of specially shaped .stockengagingportions are provided...

Anothercobject of this invention istoprov-ide aspinni'ngdevice which" is so constructedandrare ranged thatit ay be used ina conventional,

drill 1 press.

Still another object of this invention is to provide an improved spinning device in which the guide for the tubular stock is made separate from the actual spinning tool whereby the one may be replaced without replacing the other.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred form of the invention is clearly shown.

In the drawing:

Figure l is an elevational view of a preferred embodiment of the invention with parts broken away.

Figure 2 is an end elevational view showing the shape of the spinning insert.

Figure 3 is a sectional view taken substantially on line 3--3 of Figure 1.

Figure 4 is a cross-sectional view of the spinning insert taken on line 4-4 of Figure 3.

Figure '5 is. a sectional view taken substantially .Referring now to Figure :1 of the drawing whereinsthere "is shown a preferred embodiment ofxthe. invention; reference numeral It) generally designatesra holdingfixture which is provided with a spindle l2 for r-use'insmounting va'fixturein 'a'conventional. drillipress. The holding fixture or adapter .I 0 serves toremovably support'a spin- 7 ninginsert' M and apilot. element It 'as shown.

The spinning insert [4 =isuprovided withacentral cavity for receiving the stockr-to beaspun or reduced. The wali of: the cavity is provided with acplurality of substantially triangular shaped stock engaging ribs! 8 which' are arranged as best shownzirijFigurefz :ofzthe'drawing. It will be noted that by'virtuel-of the triangularshape of the stock engaging fribs; the.=base.-iportion 'of each triangle contactssthe incomiiigrstockrl lljand .as the stock is gradually reduced in diameter itimoves towards the TELPEXI'Of" the triangle with :the result that a" progressively .narrowerportionaofthe triangle -en-' 1 gages :the "stock-. Theiwall'of the :.central cavity.

is;-cuti:away-between:the ribs was shown at '23 sog-zas' to; permit the stock to expand .or. deformxintot the; reliefzrecess formed by the cutaway; portions 20.;as shown: in: Figure 5.?

For :xpurposeszaofs; illustrating athe' in'venti'on, I

have shown: an arrangement :iIlzWhiCh there are three of the stock engagingrribsr-yItshould .be

noted :that' thestock engaging ribs. comprise somewhat: lessathan oneathirdvof .the circumference with the. result that themajor portion of the stock ist-freeuto deform into-:the relief recesses. With three 'ribs; arrangedaasshown.- the stock is reduced-- andrexpandedithree :timesrfor: each revolution. of"

the spinning tool. By virtue of the above described arrangement, it is possible to operate the spinning tool at speeds in the neighborhood of 1200 R. P. M. and to reduce effectively the diameter of the stock without exerting excessively high axial pressures such as commonly required in spinning tools of the type now commonly in use in the industry.

As best shown in Figure l of the drawing, a guide ring 24 has been provided for guiding the incoming stock as it moves into contact with the spinning insert I 4. This guide ring is made separate from the spinning insert l4 so as to make it possible to replace either the guide ring or the spinning insert without necessarily replacing the other. Furthermore, the arrangement simplifies the problem of manufacturing the spinning device. The internal diameter of the ring 24 is preferably slightly greater than the external diameter of the stock to be turned so as to avoid the likelihood of seizure between the stock and the guide ring. Furthermore, the guide ring 24 is provided with cutaway portions 26 so that even though a piece of slightly oversized stock may be inserted it would be impossible for the guide ring to engage the stock throughout its entire circumference.

The guide ring 24 is clamped in place by means of the removable retainer 28 which has a screw threaded connection with the main adapter lil. One or more set screws 30 are provided as shown for engaging fiat surfaces on the insert for preventing the insert M from rotating relative to the holder or adapter l0. By removing the retainer 28 and loosening the set screws 30, it is possible to remove both the guide ring 24 and the spinning insert I4. It will be noted that when the parts are assembled for use the retainer 28 firmly clamps the guide ring against the spinning insert 14 so as to firmly hold the insert [4 in place. The adapter ID is provided with lugs 32 which engage within slots 34 provided in the outer periphery of the guidering so as to prevent relative rotation between the guide ring and the adapter and so as to accurately position the guide ring relative to the insert I4.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In combination, a forming tool for reducing stock having an axially extending cavity at least a portion of which is of progressively diminishing cross-section longitudinally of the tool, the wall of said cavity being adapted to engage and. reduce the stock upon relative rotation and axial movement toward one another of the stock and the tool, said wall being provided with a plurality of triangularly shaped stock engaging ribs with the bases of said triangles disposed adjacent the inlet of said cavity and with their vertexes extending toward the outlet of said cavity, a holder for removably supporting said forming tool, and guide means for the incoming stock removably carried by said holder, said guide means comprising a ring clamped between a portion of said holder and said forming tool.

2. In combination, a forming tool for reducing stock having an axially extending cavity at least a portion of which is of progressively diminishing cross-section longitudinally of the tool, the wall of said cavity being adapted to engage and reduce the stock upon relative rotation and axial movement toward one another of the stock and the tool, said wall being provided with a plurality of triang-ularly shaped stock engaging ribs with the bases of said triangles disposed adjacent the inlet of said cavity and with their vertexes extending toward the outlet of said cavity, a holder for removably supporting said forming tool, and guide means for the incoming stock removably carried by said holder, said guide means comprising a ring clamped between a portion of said holder and said forming tool and having a plurality of stock engaging segments provided on the inner periphery of the ring.

3. In combination, a forming tool for reducing stock having an axially extending cavity at least a portion of which is of progressively diminishing cross-section longitudinally of the tool, the Wall of said cavity being adapted to engage and reduce the stock upon relative rotation and axial movement toward one another of the stock and the tool, said wall being provided with a plurality of triangularly shaped stock engaging ribs having their vertexes extending toward the outlet of said cavity, a holder for removably supporting said forming tool, and guide means for the incoming stock removably carried by said holder, said guide means comprising a ring clamped between a portion of said holder and said forming tool and having a plurality of stock engaging segments provided on the inner periphery of the ring, the internal diameter of said guide ring being slightly greater than the diameter of the stock to be reduced.

4. In combination, a forming tool for reducing stock having an axially extending cavity at least a portion of which is of progressively diminishing cross-section longitudinally of the tool, the wall of said cavity being adapted to engage and reduce the stock upon relative rotation and axial movement toward one another of the stock and the tool, said wall being provided with a plurality of stock engaging ribs for engaging said stock, a holder for removably supporting said forming tool, and guide means for the incoming stock removably carried by said holder, said guide means comprising a ring clamped between a portion of said holder and said forming tool.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 172,443 Ide Jan. 18, 1876 2,349,168 Hill May 16, 1944 2,358,711 Hill Sept. 19, 1944 2,449,247 Paucek Sept. 14, 1948 

